4.3 Work part 1

Planning
  • Recap:  Resultant forces and graphs
  • New:  Work
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Slide 1: Slide
NatuurkundeMiddelbare schoolvwoLeerjaar 3

This lesson contains 13 slides, with interactive quizzes, text slides and 1 video.

time-iconLesson duration is: 30 min

Items in this lesson

Planning
  • Recap:  Resultant forces and graphs
  • New:  Work

Slide 1 - Slide

This graph depicts a(n)
A
acceleration
B
uniform motion
C
deceleration
D
standing still

Slide 2 - Quiz

This graph depicts a(n)
A
acceleration
B
uniform motion
C
deceleration
D
standing still

Slide 3 - Quiz

This graph depicts a(n)
A
acceleration
B
uniform motion
C
deceleration
D
standing still

Slide 4 - Quiz

This graph depicts a(n)
A
acceleration
B
uniform motion
C
deceleration
D
standing still

Slide 5 - Quiz

Fres<0
Fres>0
Fres=0

Slide 6 - Drag question

Work
Work = Force x distance
W = F x s
  • Without force there is no work
  • Without movement there is no work
  • If the force works perpendicular to the movement that does not provide work

Slide 7 - Slide

Slide 8 - Video

In which of these examples there is work being applied?
A
Arm wrestling between two people of equal strength
B
Pushing against the wall of your house
C
standing still
D
Standing on an escalator which goes upwards

Slide 9 - Quiz

Calculating Work
W = F•s

W (Work)  [J] or [Nm]
F (Force ) [N]
s (space/distance) [m]

Slide 10 - Slide

Forces of friction
During the last couple of weeks the creeks froze over so you decided to go ice skating again. The friction from the ice on your skates was very little, only 30N. You got up to a high speed and without any additional movements you glided on until you came to a standstill after a respectable distance of 70 meters.
What was the work which the ice acted upon you?

Slide 11 - Slide

What was the work that was acted upon you?
F = 30 N
s = 70 m

Slide 12 - Open question

Work
  • Will affect the speed something is travelling in

  • a negative amount of work will affect something in the opposite direction in which it is travelling (higher friction then driving forces for instance)

Slide 13 - Slide